Use random names for sinks and logs.
Use random names for sinks and logs.

Change-Id: Idb0bef2921f63ba1fdc975bc70341654ae085fdc

GoogleCloudPlatform/dotnet-docs-samples,GoogleCloudPlatform/dotnet-docs-samples,GoogleCloudPlatform/dotnet-docs-samples,GoogleCloudPlatform/dotnet-docs-samples